Angenosis Flashcards
(40 cards)
At which stage does endothelial cells barely divide?
Adult life
what are the two processes responsible for the formation of new blood vessel
vasculogensis and angiogensis
what are mural cells and why is it important?
Mural cellsare the vascular smooth musclecells(vSMCs), and pericytes of the microcirculation. They are important for vascular development and stability
which stage is responsible for the maturation of the primitive vascular system?
angiogenesis
what is another name for primitive vascular network?
capillary plexus
what is angiogensis?
The formation of vascular sprouts from pre-existing vessels
which stage of life does angiogenesis occur in?
during development and post natal
when and where is angiogenesis is regulated for a short period and then inhibited?
- when blood vessel is forming in the placenta
- when a wound is healing
- thickening of the endometrium during the mensural cycle
what are the ‘on’ and ‘off’ switches known in angiogensis?
on= angiogenesis stimulating growth factor off= angiogenesis inhibitors
how is angiogenesis turned off?
when the anti-angiogenic factors are up-regulated and overcome the on switches (pro-angiogenics)
which diseases is associated with switched on angiogenesis due to higher level of stimulators?
- cancer
- oculars disorders (diabetic retinopathy)
- plaques
- crohn’s disease
- rheumatoid arthritis (destroyed cartilage= immobility )
- obesity
- psoriasis (severe itching)
which diseases is associated with switched off angiogenesis due to higher level of inhibitors?
heart diseases
impaired vascularisation capacity
What are two diseases are a cause of neovascularization on the retina?
Age related macular degeneration
retina retinopathy
due to angiogensis, a plaque thickening the blood vessels as a result of low oxygen reach
Atherosclerotic plaques
how is angiogenesis triggered by tumour cells?
When the tumour inner cells becomes hypoxic (because it is further away from the blood vessel) it produces the angionic mediators (growth factors)= angiogenesis = production of new blood vessel= tumour gets bigger and allows the transport mechanism of metastatic spread
which peptide growth factor is involved in proliferation, migration and differentiation?
Vascular endothelial growth factor, FGF2 (fibroblast growth factor ) and PDGF (Platelet derived growth factor )
in the multi-step process of angiogenesis , what are the 3 important components?
- cells
- soluble factors
- extracellular matrix
why is VEGF important in the initiation of angiogenesis?
it regulates the vascular permeability
What are the key pro-angiogenic factors?
VEGF
ANG-1- angiopiotein 1
FGF-2-fibroblast growth factor
PDGF-platelet dervied growth factor
what leads to embryonic lathality?
loss of one VEGF allele
what stimulates VEGF mRNA transcriptions?
Growth factors and cytokines, PDGF and epidermal growth factor(PDG,EGF. TNF-a)
Which receptors VEGF binds to? What type of receptor are they?
VEGFR-1 AND VEGFR-2
Tyrosine kinase
what regulates the VEGF receptor gene expression?
hypoxia
what are the receptors angiopioetins bind to?
TIE-1 & 2 (tyrosine kinase w immunoglobulin- and endothelial growth factor (EGF)-like domains)
in endothelial cells
